Surat Al-Kahf (The Cave) - سورة الكهف

: Until, when he came to the rising place of the sun, he found it rising on a people for whom We (Allah) had provided no shelter against the sun.

: So (it was)! And We knew all about him (Dhul-Qarnain).

: Then he followed (another) way,

: Until, when he reached between two mountains, he found, before (near) them (those two mountains), a people who scarcely understood a word.

: They said: "O Dhul-Qarnain! Verily! Ya'juj and Ma'juj (Gog and Magog) are doing great mischief in the land. Shall we then pay you a tribute in order that you might erect a barrier between us and them?"

: He said: "That (wealth, authority and power) in which my Lord had established me is better (than your tribute). So help me with strength (of men), I will erect between you and them a barrier.

: "Give me pieces (blocks) of iron," then, when he had filled up the gap between the two mountain-cliffs, he said: "Blow," till when he had made it (red as) fire, he said: "Bring me molten copper to pour over it."